Apparently it was not so long ago, when he was pushing states' rights, but now, eyeing the White House and in need of support from the religious right, he's come out in support of federal action:

So much for states' rights.

Texas Governor Rick Perry (R), one of the country's most prominent
defenders of the 10th Amendment, is making an exception when it comes to
gay marriage. After initially telling reporters that it's "fine with
me" if states like New York legalize same-sex unions through their own
legislature, Perry is pulling a 180 and calling for a Federal Marriage Amendment.

Perry, who is flirting with a presidential bid, clarified his
position to Family Research Council president Tony Perkins in an
interview.

"I probably needed to add a few words after that 'it's fine with me'
and that it's fine with me that a state is using their sovereign rights
to decide an issue," he said. "Obviously gay marriage is not fine with
me. My stance hasn't changed."

Well, no, it has. His personal stance may not have changed -- he's against same-sex marriage and, if it were up to him, there wouldn't be any -- but his political stance has -- he thinks there should be a federal ban that denies states the right to legalize it on their own.

As Joe explains: "This is just more evidence of how the dominionists are forcing the GOP
presidential field to conform to their vision of a Christian theocracy."